Dispatching an ItemClick event from a chart

Question

I am trying to provide a simple drill down by getting a name
from a pie slice and then putting the slices contents in a datagrid
based on that name as a filter.
I am trying to use an event dispatcher and an event listener,
but im not exactly sure im doing it right.
The dispatcher would dispatch when something is clicked, and
the string item of what is clicked would be passed into the
remote object. (Not sure how the ItemClick string is passed
by an event)
I know i'm a newb with events.... thanks for any input.
here is the chart component
<?xml version="1.0" encoding="utf-8"?>
<mx:Panel xmlns:mx="
http://www.adobe.com/2006/mxml"
title="Defect Chart (Status not Closed)" layout="absolute"
width="100%" height="100%">
<mx:Script>
<![CDATA[
import mx.charts.ChartItem;
import mx.collections.ArrayCollection;
//Label function for the Defect Pie Chart
private function labels(dataItem:Object, field:String
,Index:int, dataPercent:Number ):String
return dataItem.BG_SEVERITY + " " + dataItem.CNT;
private function ItemClick(name:String):void
dispatchEvent(new ChartItemEvent.);
trace("event is dispatched");
]]>
</mx:Script>
<mx:PieChart id="DefectPie"
width="100%"
height="100%"
showDataTips="true"
y="40"
itemClick="{ItemClick(event.hitData.chartItem.item.toString())}"
>
<mx:series>
<mx:PieSeries id="series"
field="CNT"
nameField="BG_SEVERITY"
labelPosition="callout"
labelFunction="labels"
>
This is called in main's init()
this.addEventListener("name" , ItemClickHandler);
And this is the handler function:
private function ItemClickHandler(event:Event):void
trace(event);
dataManager.soe_bug_list_detail(event['BG_SEVERITY']);
}

Answer 1

JoeADSK,
This might sound like a bit over-kill but you might go ahead
and use a seperate EventHandler class and a DTO(Data Transfer
Object) class to accomplish the event even though you are simply
sending 1 piece of data.
Here is an example if you need one:
==Event Handler Class==
package event
import flash.events.Event;
import myApp.dto.ChartItemDTO;
public class ChartClickEvent extends Event
public var chartName:ChartItemDTO;
public function ChartClickEvent(chartName:ChartItemDTO,
type:String)
super(type);
this.chartName = chartName;
override public function clone():Event
return new ChartClickEvent(chartName, type);
DTO Class:
package myApp.dto
public class ChartItemDTO
public var name:String;
public function ChartItemDTO(name:String)
this.name = name;
Here is how you use it in your mxml for or whatever:
import event.ChartClickEvent;
import myApp.dto.ChartItemDTO;
DONT FORGET TO ADD THIS EVENT BLOCK:
<mx:Metadata>
[Event(name="chartName", type="event.ChartClickEvent")]
</mx:Metadata>
HERE IS AN EXAMPLE FUNCTION NON-WORKING===
private function setChartName(name:String):void
var chrtName:ChartItemDTO = new ChartItemDTO(name);
var chrtClickEvent:ChartClickEvent = new
ChartClickEvent(chrtName, "chartName");
dispatchEvent(chrtClickEvent);
Now this is just hacked together quickly not a working model
but you will get the idea.
Basically the event must be passed a Data Transfer Object to
hand off from the Click event.
Like I said this is over-kill but a good place to start as
you venture forth in the the Event Handling world in Flex.
Good luck, hope this helps,
Kenny